Traffic watch/pipeline folks who do not have a CFI certificate often flunk airline training because they get really rusty on a lot of stuff (not that they even knew half of it to begin with).
Really? I did aerial mapping work with Landcare for three years, moved on to check hauling, and am now flying an ATR and I never, ever had a problem with any training event or checkride. I was never a CFI either. You are either a good pilot who keeps up with his knowledge base or you are not. Flying precision grids for 6-8 hours a day makes you a real precise pilot. It is up to you if you keep up with the FAR's and general pilot knowledge.
He said they encourage all their pilots to fly IFR while relocating and to shoot approaches even when getting back from our daley routine
It is going to be up to you whether or not you do this and get what you need. I needed night to become 135 eligible. So if I was relocating, instead of heading home at the end of the day I would wait a few hours and fly back at night. Same with instrument, you can fly above or below the deck or you can file and fly in the weather. I got the time I needed to move on but I had to go the extra mile to do it. It is good experience. I would advise taking it easy on the hard IFR in a 172 though. Work your way up to hard IFR. Doing it under the hood or with someone in the cockpit with you is a lot easier than single pilot IFR in the real stuff. Knowing what I know now I would never do some of the things I did. If I am going to fly a 172 I want a couple of thousand feet of clear air under the deck or localized IFR so that I can escape if necessary. Good luck with your choice.